The 2013 version of the index was released on Monday by the London-based Mo Ibrahim Foundation, which makes information on governance quality in Africa freely accessible in the interests of good governance on the continent.
The index uses a methodology specially developed by a team from the Kennedy School of Government at Harvard University in the US, with the help of an advisory council of African academics.
It measures country and regional performance across four main categories - safety and rule of law; participation and human rights; sustainable economic opportunity; and human development - breaking down into 14 sub-categories and 88 component indicators.
South Africa is one of eight countries to have remained consistently in the index's top 10 since 2000 - along with Botswana, Cape Verde, Ghana, Mauritius, Namibia, Seychelles and Tunisia - although its ranking in the index has dropped by one place.
The country's overall scores of 71.3 (out of a possible 100) is higher than the African average of 51.6, as well as the regional southern African average of 59.2.
South Africa ranks its highest (3rd out of 52 countries, with a score of 73.1) in the category of participation and human rights - but has recorded its biggest decline in this category since 2000, dropping two places in the rankings and shedding 4.6 points in its score.
The country's lowest ranking (7th, scoring 69.8) is for safety and rule of law, where it has dropped one place, shedding 3.2 points, since 2000.
For sustainable economic opportunity, South Africa ranks 5th with a score of 65.1, dropping one place but improving its score by 5.8 points since 2000. And for human development, the country ranks 6th with 77.4 points, down by two places but up by 4.4 points since 2000.
Overall, the 2013 index shows that Africa has made progress in governance in the last 13 years, with 94% of Africans living in a country that is better governed than in 2000. (The 6% of people living with governance has deteriorated since 2000 live in Guinea-Bissau, Madagascar, Eritrea, Somalia, Libya and Mali.)
Southern Africa remains the top performing region in the 2013 index, with eight out of 12 countries in the region scoring above the continental average overall, five countries ranking in the top 10 and just one country, Zimbabwe, ranking in the bottom 10.

South Africa remains in fifth place in the 2013 Ibrahim Index of African Governance having improved it's overall governance score from 70.7 to 71.3 out of a possible 100 since the index was first launched in 2007 with data covering the period 2000 onwards The top 10 African countries for governance according to the latest index are scores in brackets Mauritius 82.9 Botswana 77.6 Cape Verde 76.7 Seychelles 75 South Africa 71.3 Namibia 69.5 Ghana 66.8 Tunisia 66 Lesotho 61.9 and Senegal 61